| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.phoenix.query; |
| |
| import org.apache.hadoop.hbase.HConstants; |
| import org.apache.hadoop.hbase.TableName; |
| import org.apache.hadoop.hbase.TableNotFoundException; |
| import org.apache.hadoop.hbase.client.HTableInterface; |
| import org.apache.phoenix.jdbc.PhoenixDatabaseMetaData; |
| import org.apache.phoenix.schema.stats.GuidePostsInfo; |
| import org.apache.phoenix.schema.stats.GuidePostsKey; |
| import org.apache.phoenix.schema.stats.StatisticsUtil; |
| import org.apache.phoenix.util.SchemaUtil; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.IOException; |
| import java.util.Objects; |
| |
| /** |
| * {@link PhoenixStatsLoader} implementation for the Stats Loader. |
| */ |
| class StatsLoaderImpl implements PhoenixStatsLoader { |
| |
| private static final Logger LOGGER = LoggerFactory.getLogger(StatsLoaderImpl.class); |
| |
| private final ConnectionQueryServices queryServices; |
| |
| public StatsLoaderImpl(ConnectionQueryServices queryServices){ |
| this.queryServices = queryServices; |
| } |
| |
| @Override |
| public boolean needsLoad() { |
| // For now, whenever it's called, we try to load stats from stats table |
| // no matter it has been updated or not. |
| // Here are the possible optimizations we can do here: |
| // 1. Load stats from the stats table only when the stats get updated on the server side. |
| // 2. Support different refresh cycle for different tables. |
| return true; |
| } |
| |
| @Override |
| public GuidePostsInfo loadStats(GuidePostsKey statsKey) throws Exception { |
| return loadStats(statsKey, GuidePostsInfo.NO_GUIDEPOST); |
| } |
| |
| @Override |
| public GuidePostsInfo loadStats(GuidePostsKey statsKey, GuidePostsInfo prevGuidepostInfo) throws Exception { |
| assert(prevGuidepostInfo != null); |
| |
| TableName tableName = SchemaUtil.getPhysicalName( |
| PhoenixDatabaseMetaData.SYSTEM_STATS_NAME_BYTES, |
| queryServices.getProps()); |
| HTableInterface statsHTable = queryServices.getTable(tableName.getName()); |
| |
| try { |
| GuidePostsInfo guidePostsInfo = StatisticsUtil.readStatistics(statsHTable, statsKey, |
| HConstants.LATEST_TIMESTAMP); |
| traceStatsUpdate(statsKey, guidePostsInfo); |
| return guidePostsInfo; |
| } catch (TableNotFoundException e) { |
| // On a fresh install, stats might not yet be created, don't warn about this. |
| LOGGER.debug("Unable to locate Phoenix stats table: " + tableName.toString(), e); |
| return prevGuidepostInfo; |
| } catch (IOException e) { |
| LOGGER.warn("Unable to read from stats table: " + tableName.toString(), e); |
| return prevGuidepostInfo; |
| } finally { |
| try { |
| statsHTable.close(); |
| } catch (IOException e) { |
| // Log, but continue. We have our stats anyway now. |
| LOGGER.warn("Unable to close stats table: " + tableName.toString(), e); |
| } |
| } |
| } |
| |
| /** |
| * Logs a trace message for newly inserted entries to the stats cache. |
| */ |
| void traceStatsUpdate(GuidePostsKey key, GuidePostsInfo info) { |
| if (LOGGER.isTraceEnabled()) { |
| LOGGER.trace("Updating local TableStats cache (id={}) for {}, size={}bytes", |
| new Object[] { Objects.hashCode(this), key, info.getEstimatedSize()}); |
| } |
| } |
| } |